There was no evidence found of any airframe failure or system malfunction prior to or during the flight. The pilot had no IFR flight experience and was not instrument qualified, and the aircraft was not equipped for IFR flight. When the pilot departed Temagami, meteorological conditions were favourable for VFR flight. However, conditions deteriorated on the intended route along the Ottawa River and became conducive to whiteout. As the pilot usually preferred to follow rivers at low altitude, it is likely that he lost visual reference when flying over the middle of Holden Lake, which was snow-covered and shrouded in fog. The 30 left-roll attitude of the aircraft and the difference between the intended route and the aircraft heading on impact suggest that the pilot was attempting to execute a turn, probably to return to more favourable weather. With visibility about one-half mile and whiteout conditions preventing the pilot from assessing his height above ground, the aircraft probably descended in a turn until it struck the frozen surface of the lake. Use of the seat-belt probably would have lessened the severity of the pilot's injuries.2.0 Analysis There was no evidence found of any airframe failure or system malfunction prior to or during the flight. The pilot had no IFR flight experience and was not instrument qualified, and the aircraft was not equipped for IFR flight. When the pilot departed Temagami, meteorological conditions were favourable for VFR flight. However, conditions deteriorated on the intended route along the Ottawa River and became conducive to whiteout. As the pilot usually preferred to follow rivers at low altitude, it is likely that he lost visual reference when flying over the middle of Holden Lake, which was snow-covered and shrouded in fog. The 30 left-roll attitude of the aircraft and the difference between the intended route and the aircraft heading on impact suggest that the pilot was attempting to execute a turn, probably to return to more favourable weather. With visibility about one-half mile and whiteout conditions preventing the pilot from assessing his height above ground, the aircraft probably descended in a turn until it struck the frozen surface of the lake. Use of the seat-belt probably would have lessened the severity of the pilot's injuries. 3.0 Conclusions 3.1 Findings The pilot was certified and qualified for the flight in accordance with existing regulations. The pilot had no IFR flight experience and was not instrument qualified. The aircraft was certified, equipped, and maintained in accordance with existing regulations and approved procedures. There was no evidence found of any airframe failure or system malfunction prior to or during the flight. The weight and centre of gravity were within the prescribed limits. Meteorological conditions at the point of departure were favourable for VFR flight. Meteorological conditions deteriorated en route and were conducive to whiteout. The snow-covered surface of the lake was covered with fog, reducing visibility below VFR minima. Visibility of about one-half mile and whiteout conditions prevented the pilot from assessing his height above ground, and the aircraft descended in a turn until it struck the frozen surface of the lake. Use of the seat-belt probably would have lessened the severity of the pilot's injuries. 3.2 Causes The pilot encountered unfavourable weather conducive to whiteout, and lost visual reference with the ground, thereby reducing the pilot's ability to determine his height above ground. The aircraft descended in a turn until it struck the frozen surface of the lake. The Board has no aviation safety recommendations to issue at this time.4.0 Safety Action The Board has no aviation safety recommendations to issue at this time.